Plate locating mechanism for stereotype plate finishing machine



C. S. CRAFTS July 19, 1960 PLATE LOCATING MECHANISM FOR STBREOTYPE PLATEFINISHING MACHINE Filed April 15, 1957 8 Sheets-Sheet 1 NVELNTOR.

I CURTI$ 5. CRAFTS E; M, @114 M TTYS.

July 19, 1960 c. s. CRAFTS 2,945,284

PLATE LOCATING MECHANISM FOR STEREOTYPE PLATE FINISHING MACHINE FiledApril 15, 1957 8 Sheets-Sheet 2 lwvsN'rolb CURTIS S. CRAFTS ml by M, @m,uhz/afig ATTYS. v;

y 1 c. s. CRAFTS 2,945,284

PLATE LOCATING MECHANISM FOR STEREOTYPE PLATE FINISHING MACHINE FiledApril 15, 1957 v 8 Sheets-Sheet 5 INVENTOR. CURTIS S. CRAFTS 25 v M #M/4/ July 19, 1960 c. s. CRAFTS 2,945,284

PLATE LOCATING MECHANISM FOR STEREOTYPEZ PLATE FINISHING MACHINE FiledApril 15, 195"! 8 Sheets-Sheet 4 INVENTOR. CURTIS S. CRAFTS nlmhl ATTYs,

BY Ma, #MfA/vi C. S. CRAFTS July 19, 1960 PLATE LOCATING MECHANISM FORSTEREOTYPE PLATE FINISHING MACHINE 8 Sheets-Sheet 5 Filed April 15, 1957INVENTOR CURTIS S. CRAFTS b m 1% V5 A-rws- C. S. CRAFTS July 19, 1960PLATE LOCATING MECHANISM FOR STEREOTYPE PLATE FINISHING MACHINE 8Sheets-Sheet 6 Filed April 15, 1957 INVENTOR. CURTIS S, CRAFTS 15'- I14, ATTY$ July 19, 1960 c. s. CRAFTS 2,945,284

PLATE LOCATING MECHANISM FOR STEREIOTYPE PLATE FINISHING MACHINE;

Filed April 15, 1957 a Sheets-Sheet 7 F ji W//////% A f/// as INVENTOR.CURTIS S. CRAFTS a M g 4 1 f 4 L ATTYS.

C. S. CRAFTS July 19, 1960 PLATE LOCATING MECHANISM FOR STEREOTYPE PLATEFINISHING MACHINE Filed April 15, 1957 8 sheets-sheet 8 INVENTOR CURTISS. CRAFTS M; ,MMgM Q I Arms.

United States Patent i PLATE LOCA'I'ING MECHANISM FOR STEREU- TYPE PLATEFINISHING MAC Curtis S. Crafts, Oak Park, 111., assignor to Mickie-Goss-Dexter, In'corporated, Wilmington, Del., a corporation of Delaware FiledApr. 15, 1957, Ser. No. 652,759

10 Claims. (Cl. 29- -21) This invention relates to stereotype printing,and more particularly to a method and means for making stereotypeprinting plates used in the printing of tabloid news papers and formilling tension lock-up pockets in the underside of such printingplates.

Modern newspapers are, generally speaking, given a format in either oftwo sizes, namely, full or regular' page size newspapers and half-sizenewspapers known as tabloids. Heretofore in' the printing of tabloidnewspapers it has been the practice to use full size semicylindricalplates, 'each full size plate bearing the impression to print twotabloid pages.

In color printing processes, the individual colorsare printed inseparate impressions and by plates prepared especially for a particularcolor. Four colors are commonly used and they are individually printedsuccessively on the moving web in newspaper presses, the last colorusually being black. The color plate must ,be'accurately positioned onthe printing cylinder so that each color will register accurately withpreviously printed colors in order to produce a satisfactoryreproduction. It is thus necessary for the printing cylinder to includemeans for adjusting the position of the plate relative to the cylinderso that it will register accurately with the previously printed colors.1

In the printing of tabloid size newspapers, the stereotype printingplate bearing the impression for the front hot news page of thenewspaper, in the ordinary press, also bears the impression to print theback page of the paper, copy for which may include an ad in a particularcolor. The news content of the front page often must be changed fordifferent editions, but in most instances from edition to edition theback page or at least the color portion remains the same. Therefore,when the news changes, the entire full size plate, including thatportion of the plate which bears the impression to print the back page,will have to be replaced. This is wasteful in terms of material andlabor cost.

Furthermore, when a new full size plate containing later news copy onone half and the same color copy on the other half is prepared, it islikely that the color copywill not be in exactly the same location-onthe plate with respect to the plate lock-up mechanism, as it was in theprevious plate. Therefore, the new plate will have to be readjusted onthe printing cylinder so that the color will be in register withpreviously printed colors before the later edition can be run off. Thisadjusting is tedious and time consuming, thus contributing to highercosts. Changes in position of the news copy on the new plate and printedpage will not be noticeable and can be disregarded, but the color platemust be registered within a small fraction of an inch so that the colorswill not be over printed.

It is a principal object of the present invention to provide a methodand means for preparingtabloid page size stereotype printing plates forprinting tabloid newspapers. With the stereotype plate prepared inaccordice Patented July 19, 1960 ance with this invention, tabloidnewspapers may be printed more economically, for these wastefulpractices are eliminated. Thus while the major part of the tabloidnewspaper may be printed in conventional fashion, with full sizeprinting plates bearing the impression of two tabloid pages, those pagesof the newspaper requiring change from edition to edition may be printedby means of individual tabloid size plates.

More specifically, it is an object of the present invention to provide amethod for making tabloid stereotype printing plates, involving thesteps of casting a full size semi-cylindrical stereotype plate with thetype impression on the periphery of it to print two tabloid pages andfinishing the underside of the plate; cutting rows of tension lock-uppockets adjacent the lateral edges of the full-size plate; separatingthe plate in two, to form two individual tabloid size printing plates;and cutting tension pockets adjacent the newly sawed edge of theseindividual plates. During this cutting operation the plate is accuratelylocated by means of the previously cut row of lock-up pockets, to insurethat the new row of pockets is correctly positioned on the underside ofthe tabloid plate.

Another and a principal object of this invention is to provide apparatusfor milling tension lock-up pockets in the underside of such individualtabloid size printing plates. A more detailed and related objectthereto, is to provide plate locating mechanism for precisely andaccurately positioning the plate during the milling operation. Asdescribed hereinbefore, in one aspect the invention is concerned withthe preparation of individual tabloid size printing plates by separatingor sawing a full size plate in two, this fullsize plate havingpreviously been processed to form rows of tension pockets in'thefinished underside of the plate, thus leaving the individual plate witha single row of tension pockets adjacent one It is an object hereof toutilize this row of its edges. of pockets in the individual tabloid sizeplate, for locating the plate during the operation of cutting the secondrow of pockets in it, so that the parallel rows of pockets in thefinished plate are spaced accurately. Other objects' will appear fromthe following description taken in connection with the accompanyingdrawings, in which:

Figures 1 and 2 are perspective views of semi-cylindrical or full sizestereotype printing plates; 7

'Fig. 3 is a'perspective view of a tabloid size stereotype printingplate; I

Fig. 4 is a perspective view of a machine for milling tension lock-uppockets in stereotype printing plates;

Fig. 5 is a section taken through the machine of Fi g. 4 illustratingthis machine equipped with a locating mechanism for tabloid plates;

Figs. 6-9 are detail views illustrating this locating mechanism;

Fig. 10 is a section taken through the machine of Fig. 4 illustratingthis machine equipped with an alternative form of locating mechanism fortabloid plates;

Figs. 11-17 are detail views illustrating this alternative locatingmechanism; and

Figs. 18-21 are views illustrating a further alternative form of platelocating mechanism.

While the invention is shown and described in detail with reference toparticular embodiments thereof, there is no intention that it thus belimited. on the contrary, it is intended to cover all modifications,alternative constructions and equivalents falling within the spirit andscope of the invention as defined in the appended claims.

Referring now to the drawings, Figure 1 illustrates a full size,semi-cylindrical, stereotype printing plate 10. This plate might beused, for example, in the printing of a full size newspaper page in oneof the dailies printed in chined, insertable bodies 50, 51 carriedwithin cavities or recesses 52, 53 formed in the saddle. The bodiesemployed to support the fingers are made of a light metal and bolted inplace as shown in Fig. 6, and in the present instance comprise U-shapedsegments 54, 55 presenting surfaces 56, 57 conforming to the outersurface of the saddle and forming a portion of the same. In order tomore precisely locate the plate, the hooks 42, 43 taper to a fine edge60 and thus are shaped to neatly fit in the notched side wall 61 of therespective tension pocket. Opposite this edge. on what may be termed theback 62, the hook is formed with a flat area 63 arranged, when thefinger is raised to operative position as shown in Fig. 6, to abut ameeting planar surface 64 formed in the insertable body on which thefinger itself is mounted. The arrangement is such as to back up andrigidly or firmly hold the hook upright once it has been manually liftedto extend above the outer surface of the saddle.

The hooks 42, 43 are operated independently. To maintain each locatinghook upright, or in the alternate position below the surface of thesaddle, the hook is fashioned with a nose portion 65, 66 which bearsagainst a fiat spring 67, 68 attached to the insertable body bolted inthe saddle. 'The pressure of the spring is sufi'icient to hold the hookin either position while still permitting the hook to be shiftedmanually, and with reasonable ease, from one position to the other.

As hereinbefore described, the single biasing finger 44 whichfaces-these hooks and engages the edge'of the plate at a point betweenthem, applies spring pressure for holding the plate against the hooks.In the operation of the milling machine, after the plate is located onthe machine saddle it is held securely during the milling operation bymeans of the clamping mechanism with which the machine is equipped. Asshown in Fig. 6, the clamps 29 expand into engagement with the plate andurge it against the saddle. The single biasing finger 44 engaging theedge of the plate, supplies means for holding the plate against movementwhile clamping is applied. For this purpose, the biasing finger 44 isrotatably mounted on a shaft 70 which in turn is journalled inthe crownof the saddle. A control handle 82 for turning the shaft 70 and raisingand lowering the biasing finger 44 from operative to inoperativeposition is attached to one end of the shaft, outside of the saddle.

To supply the spring pressure for urging the biasing finger 44 against atabloid page size plate placed on the saddle, a torsion spring 71surrounding the shaft and having one end 72 anchored thereto isemployed. The other end 73 of the spring is formed with a straightportion 74 parallel to the shaft so that it will bear against the backof the holding or biasing finger 44 when the shaft is rotatedcounterclockwise as shown in Fig. 9. In the present instance, thebiasing finger 44 is held on the shaft 71 between a collar 75 anda pin76 extending part way through the shaft and it is freely rotatable to alimited extent on the shaft.

For mounting the shaft 70 on the saddle, as shown in Fig. 8, one end ofthe shaft is supported in the end wall 78 of the saddle, and the otherend in a boss 79 formed in the saddle casting. To prevent endwisemovement of the shaft it is held in position by a collar 80 on theinside of the end wall '78 and a clevis 81. pinned to the shaft on theoutside of the saddle. A locking handle 82, by means of which the shaftmay be rotated and thus the biasing finger 44 raised and lowered fromoperative to inoperative position, is mounted on a pin 83 in the clevis.This locking handle is pivotally supported on the pin so that it mayswing outwardly as viewed in Fig. 8.

Motion of the shaft in one direction is transmitted to the biasingfinger 44 rotatably mounted on the shaft by means of the pin 76 fixed tothe shaft and a segmental boss 84 on the hub of the finger 44. 'Withthis arrangement, the shaft70 when turned clockwise as shown in Fig. 9by the handle 82, transmits motion to the biasing finger 44 to lower it.When the handle is turned counterclockwise as shown in Fig. 9, thetorsion spring, bearing as it does against the biasing finger 44, actsto urge the said finger against the edge of the printing plate on thesaddle. For example, as shown in Fig. 6, the finger 44 forces the platetowards the right until the face of the hook 43 engages the side wall 61of the tension pocket in which it is received, locating and locking theplate in position. To stress the torsion spring 71, the control handleis turned approximately 30 beyond the point at which the biasing fingerengages the plate. tion of the handle corresponding to the initialengagement of the biasing finger 44 with the printing plate isapproximately vertical, the solid line position of Fig. 9. The downposition (dotted) of the handle as shown in this figure and Fig. 16corresponds approximately to that position of the handle when thebiasing finger lies within the saddle. The full line upright position ofthe handle 82. in Fig. 9 is that position the handle assumes to stressthe torsion spring and upon reaching this latter position, the top ofthe handle is moved away from the saddle, as shown in the dottedposition of Fig. 8, effecting engagement of the lower end of the control'handle with a locking lug 86. The friction between the parts, and theconstant pressure exerted by the spring holds these parts in lockedposition.

To release the holding finger 44, as for example fol lowing thecompletion of a milling operation on a tabloid page size plate, theupper end of control handle 82 is pivoted towards the saddle to separatethe lower end of the handle from engagement with the locking lug 86. Thecontrol handle 82 and the shaft 7% are then free to rotate first underthe urging of the torsion spring 71, and after the stress in the springhas been relieved, by turning the shaft further in a counterclockwisedirection by means of the control handle to the down (dotted) positionof Fig. 9. The said further turning of the shaft causes pin 76 to engagesegmental boss 84 and this carries finger 44 into retracted position.

The machine shown in Fig. 4, is provided with milling heads 23 (Fig. 5)located to mill tension lockup pockets in both edges of a full sizeplate supported on the saddle of the machine. With an individual tabloidsize plate precisely located on the saddle as shown in Fig. 6, by meansof the locating mechanism 46 hereinbefore described, a row of tensionpockets may be cut adjacent the newly sawed edge of this plate. Theactual milling of the pockets is carried out in a conventional fashion,using the milling head arrangement found on the machine. The millingheads of this arrangement pivot into contact with the underside of theplate clamped on the saddle to mill the pockets, the distance betweenthese pockets being precisely determined in relation to the previouslymilled row of pockets on the other edge of the plate.

In the form of the invention illustrated in Figs. 5-9, in the crown ofthe saddle the locating mechanism 40 is arranged in such a way that theparts may be disposed in a position within the saddle so as not tointerfere with a tension pocket milling operation carried out on a fullsize plate. Moreover, the mechanism components may be raised manually toan erect or upright position extending above the surface of the saddleto engage an individual tabloid size plate for locating the same on thesaddle while a second row of tension pockets is formed adjacent thenewly sawed edge of this plate.

Further in accordance with the invention, an alternative form for thelocating hook and biasing finger arrangement shown in Figs. 5-9, isillustrated in Figs. 10-17. The same general arrangement of locatinghooks and biasing finger is employed for engagement within the tensionlockup pockets adjacent the finished edge of the tabloid plate, andengaging the edge of the plate to insure that the hooks are properlyseated within the ten SlOIl pockets and to prevent movement of the platewhile clamping is applied. While the same general arrange- The posi-vment is used, the construction ofthe hooks-and biasing finger differssomewhat from that employed in the previously described form. The saddle85 of a milling machine like that illustrated in Fig. 4, is againprovided with a plurality of cavities along the crown to accommodate thelocating hooks 86, 87. The locating hooks, in the present instance, areplunger-like and are urged towards their hidden position by coil springs88, 89 compressed between the inside wall of the saddle and flanges 90,91 borne mediately of the hooks themselves. while ordinarily the hooksare retracted by the coil springs and forced downwardly to their loweredposition within the saddle, these hooks may be raised to an operativeposition by means of cams 93 operable from the outside of the saddle.For convenience, in the exemplary form of the invention shown, a key orthe like is used for turning the cams and raising the hooks.Accordingly, the cams are non-rotatably mounted on rods 94, 95 supportedon the saddle, and formed on one end with a cross tongue 97 (Figs. 10,15) to be received in a slotted key 98. In the arrangement illustrated,the rods 94, 95 are rotatably mounted within the saddle casting on achord of the cylindrical surface of the saddle, and the surface. of thesaddle bored to make the ends of the mounting rods ac; cessible. A keyfor turning each mounting rod may therefore be inserted within therespective bore in the saddle. The cams carried by the rods turn withthe rod to elevate the plunger-like locating hooks and compress thesprings. Upon rotation of the mounting rod and cam in the oppositedirection, the coil springs act to retract the hooks.

Companion to each locating book 86, 87, in the form of the inventionillustrated in Figs. -17, is a biasing finger 99, 99 mounted to beengageable with the edge of a tabloid printing plate placed on thesaddle for forcing the plate onto the locating hooks. These fingers 99,99' are mounted on a shaft 100 in turn supported by the saddle, in asimilar way to the arrangement employed in the form of the inventiondescribed previously. This shaft 100 may be rotated by a control handle101 attached to a collar 112 which is pinned to the end of the shaft andthe shaft is journalled in the saddle in a boss 102 and in the end wall103 of the saddle casting. In a manner quite similar to that describedpreviously, each biasing finger is acted upon by torsion springs 104,105, which raise the respective biasing finger to operative positionabove the surface of the saddle, and then upon additional rotation ofthe shaft act to force the finger into engagement with the edge of theplate to force the plate into engagement with the locating hooks 86, 87and to secure proper seating of the hooks within the tension pockets inthe underside of the plate.

Rotating the shaft 100 clockwise as viewed in Fig. 16 by means of thecontrol handle 101, lowers the biasing fingers 86, 87 to a positionbelow the surface of the saddle. The control handle movement and turningmotion of the shaft in this direction is transmitted to these fingers bypins 106, 106' fastened in the shaft and, as shown in Figs. 11 and 12,engaging flats provided by segmental bosses 107, 108, carried on thesides of eachof the fingers. These fingers 99, 99 are free to rotate onthe shaft 100. This is for the purpose of permitting the shaft to beturned by means of the control handle,

angularly beyond the point at which the biasing fingers are positionedin engagement with the plate in order to stress the torsion springswhich, in turn, apply spring force to these biasing fingers to urge thebiasing fingers against the plate. As shown in Fig. 14, a simple meansfor locking the handle in position to stress the springs may be providedby offset shoulders 110, 111 carried respectively on the saddle castingand collar 112.

As in the form of the invention described earlier in connection withFigs. 5-9, the locating mechanism found on the crown of the saddle maybe positioned below the surface of the saddle in an inoperativeposition, so as not -to interfere with a full size printing-plateclamped on the saddle. Moreover, the locating hooks and companionbiasing fingers may be easily shifted to an operative position extendingabove the surface of the saddle, for engagement with a tabloid sizeprinting plate, located on one side of the saddle in position to receivethe second row of tension pockets adjacent the newly sawed edge of theplate. I Thus, it will be readily observed, a machine for millingtension pockets in full size printing plates may be equipped toaccommodate tabloid size plates while still allowing its use in themanner originally intended. This increases the versatility of themachine and enables its use in the preparation of individual tabloidsize printing plates, in the manner and by the method for preparing suchplates described hereinbefore.

Further in keeping with the invention, means may be provided asillustrated in Figs. l8-21, for locating two tabloid plates obtained bysawing a full size plate in sections, on the saddle during the millingoperation wherein a second row of pockets is milled adjacent the newlysawed edge of the respective plates. In this instance, the platelocating mechanism 11? is arranged so as to position the two plates sothat one is on each side of the curved saddle, and by means of thelocating mechanism the plates are positioned so that the new pockets 122when cut by the milling cutters 23 as shown in Fig. 18, are accuratelyspaced from the existing pockets 122'. Referring to Fig. 18, it will beseen that this locating mechanism embodies an assembly includinglocating hooks 120, 121 arranged in pairs, one pair on each side of thelongitudinal center line of the saddle 24. The hooks of each pair aremounted to engage the existing pockets 122 in tabloid plates on therespective side of the saddle, for positioning the plates so that asecond row of pockets can be milled along the sawed straight edge of theplate. In the present instance, as shown in Fig. 20, the hooks of eachpair are spaced longitudinally on thesaddle so as to engage in the endpockets of the plates. The locating hooks 120, 121, as in the previousforms of the invention, are pivotally mounted so that they maybepositioned below the surface of the saddle within a cavity 124 or may bemanually lifted to a position where they extend above the surface of thesaddle to engage the tabloid plates, in which position the hooks areshown in Fig. 18. Referring to the same figure, the locating hooks aresupported on mounting rods 126, 127 which are carried by a machinedsegment 128 which itself is mounted on the top of the saddle 24 within atransverse cavity 129.

The outside surface of the segment 128 conforms to the surface of thesaddle and provides a continuation thereof and the segment may itself berecessed to provide the cavity 124 for receiving the locating hooks 120,121. The opposite end walls 130 of the cavity or recess within thesegment 128 are vertical and accurately machined to provide a stopagainst which the back 131 of each locating finger bears when in theoutward position depicted in Fig. 18. To resiliently maintain thelocating fingers in either position, a nose portion 132 is providedwhich bears against a flat spring 133.

In this form of the invention, a wedge 134 is employed for forcing thetabloid page size plates against the locating hooks, to prevent shiftingof the plates on the saddle when clamping is applied. As shown in Figs.8, 18 and 21, this wedge is mounted to move vertically within a slideprovided in a bracket 135 mounted above the crown of the saddle, forexample, by means of bolts, upon the arcuate, rigid backing supports forthe plate clamps 29 provided for clamping the plate on the saddle of themachine. The wedge 134 may be forced against the plates by means of awedge handle 136. This wedge handle may actuate the wedge by means of apin 137 which is fastened to the wedge handle and extends throughopposite slightly enlarged openings 138 which are provided on ears 139above the body of the wedge.

This connection provides a limited range of movement of the wedge handle136 from a horizontal position, as shown in solid lines in Fig. 19, toan angularly extending raised position as shown in dash-dot lines inthis same figure. Springbiased detents 14b and detent wells 141 (Fig.21) are employed for holding the wedge in its rased position spaced awayfrom the saddle so as not to interfere with the normal operation of themachine to mill full size stereotype plates.

With this form of the invention, both tabloid plates formed from onesemi-cylindrical plate may be positioned on the machine Without turningeither plate end for end on the saddle. A plate'finishing machine asshown in Figure 4 may include features for use in preparing full sizesemi-cylindrical plates for printing color, such as image registeringmechanism, plate stops and skewing devices. Ordinarily such a machinealso provide a cutteron each side of the machine which trims one end ofthe full size plate at both corners for sidelay register purposes. Withthe locating mechanism here shown, a

'tabloid plate be positioned on the saddle in the same endwise relationto that it originally held while part of the full size plate, butshifted to a position on the opposite side of the saddle. When thetabloid plate is so positioned, the trimming mechanism with which themachine is ordinarily equipped may be utilized for trimming th othercorners for registering purposes.

1 I claim as my invention:

1. The method of making tabloid stereotype printing plates comprisingthe steps of: casting a full size stereotype printing plate with theimpression for two tabloid pages on the periphery of it; cutting rows oftension pockets adjacent the lateral edges of the full size plate;separating the full size plate half lengthwise thereby forming twoindividual tabloid plates; and cutting a second row of tension pocketsadjacent the newly made edges of the original halves now constitutingtabloid printing plates, thereby providing the plates with tensionpockets adjacent both lateral edges for cooperation with tension lock-upmechanism provided on the printing cylinder.

2. The method of making partial size stereotype printing plates,comprising, the steps of casting a full size stereotype printing platewith the impression for at least one partial'size page on the peripheryof it; cutting a row of tensionpockets adjacent at least one of thelateral edges of this full size plate and on the underside of the plateportion bearing the page impression; separating the full size plate inhalf lengthwise thereby forming individual plates; and cutting a secondrow of tension pockets adjacent the newly made edge of the individualplate hearing the page impression thereby providing said plate withtension pockets adjacent both lateral edges, locating the plate for thelatter cutting operation by means of the row of tension pocketspreviously cut.

3. In a machine for milling tension lock-up pockets in semi-cylindricalprinting plates, the combination comprising, a saddle providing asemi-cylindrical reference surface conforming to the curvature of suchplates, means overlying said reference surface and engageable with aplate carried on said reference surface for clamping said plate on saidsaddle, and means for positioning a tabloid size plate having the samecurvature as the semi-cylindrical plate on said saddle while saidclamping means is engaged, said positioning means including a row ofplate locating members carried on the crown of the saddle and extendingabove the surface of the latter to be received in tension pocketsadjacent one edge of the tabloid size plate so as to define the desiredlocation for the latter.

4. In a machine for milling tension lock-up pockets in semi-cylindricalprinting plates, the combination comprising, a saddle providing asemi-cylindrical reference surface conforming to the curvature of theplates, means overlying said reference surface and engageable with aplate carried on said reference surface for clamping sa d plate on saidsaddle, and means for positioning a tabloid size plate having the samecurvature as the semi-cylindrical plate on said saddle while saidclamping means is engaged, said positioning means including means providing a row of recesses along the crown of the saddle, plate locatingmembers in each of said recesses, and means for pivotally mounting saidmembers for movement between a position within said recess to a positionprojecting above the saddle surface, whereby said members are receivablein tension pockets adjacent one edge of the tabloid size plate so as todefine a desired location for the latter.

5. In a machine for milling tension lock-up pockets in semi-cylindricalprinting plates, the combination comprising, a saddle providing asemi-cylindrical reference surface conforming to the curvature of theplates, means overlying said reference surface and engageable with aplate carried on said reference surface for clamping said plate on saidsaddle, means for positioning a tabloid size plate having the samecurvature as the semi-cylindrical plate on said saddle while saidclamping means is engaged, said positioning means including plateengaging hooks mounted along the crown of said saddle and located forinsertion in tension pockets adjacent one edge of the tabloid size plateso as to define a desired location for the latter, and a resilientlybiased finger supported on the crown of said saddle in association witheach of said hooks for engagement with the said one plate edge adjacentthe tension pockets and acting on said one plate edge to urge the plateagainst said hooks so it is held solidly against movement.

6. In a machine for milling tension lock-up pockets in semi-cylindricalprinting plates, the combination comprising, a saddle providing asemi-cylindrical reference surface conforming to the curvature of theplates, means overlying said reference surface and engageable with aplate carried on said reference surface for clamping said plate on saidsaddle, and means for positioning a tabloid size plate having the samecurvature asthe semi-cylindrical plate on said saddle while saidclamping means is engaged, said positioning means including plateengaging members mounted along the crown of said saddle to extend abovethe surface of the latter and located for insertion in tension pocketsadjacent one edge of the tabloid size plate so as to define a desiredlocation for the latter, and resilient means supported on the crown ofsaid saddle in association with said members for engagement with theplate edge adjacent the tension pockets and acting on said. plate edgeto urge the plate against said members so it is held solidly againstmovement.

7. Ina machine for milling tension lock-up pockets in semi-cylindricalprinting plates, the combination comprising, a saddle providing asemi-cylindrical reference surface conforming to the curvature of theplates, means overlying said reference surface and engageable with aplate carried on said reference surface for clamping said plate on saidsaddle, means for positioning a tabloid size plate having the samecurvature as the semi-cylindrical plates on said saddle while saidclamping means is engaged, said positioning means including meansproviding a pair of recesses longitudinally spaced along the crown ofsaid saddle and on one side of the center line thereof, a plate locatinghook pivotally mounted in each recess for movement from a position insaid recess to an upright position extending above the saddle surfacewherein said locating hooks are receivable in tension pockets adjacentone edge of the tabloid size plate, said recesses being arranged todefine a desired location for the plate on the saddle, and means carriedby the saddle and acting on said one edge of a tabloid plate to urgethe' plate solidly against said locating hooks, and thereby hold theformer against movement including means providing a recess in the crownof said saddle on the opposite side of the center line from saidfirst-mentioned recesses and between the latter, a shaft mounted in saidlast-named recess, and a spring biased finger mounted on said shaft andmovable into resilient engagement with said one edge of the plate.

8. In a machine for milling tension lock-up pockets in semi-cylindricalprinting plates, the combination com-. prising, a saddle providing asemi-cylindrical reference surface conforming to the curvature of theplates, means overlying said reference surface and engageable with aplate carried on said reference surface for clamping said plate on saidsaddle, and means for positioning a tabloid size plate having the samecurvature as the semi-cylindrical plate on said saddle While saidclamping means is engaged, said positioning means including meansproviding a pair of recesses longitudinally spaced along the crown ofsaid saddle and on one side of the center line thereof, a plate locatinghook mounted in each recess for movement from a position in said recessto an upright position extending above the saddle surface wherein theplate locating hooks are receivable in tension pockets adjacent one edgeof the tabloid size plate, said recesses being arranged to defineadesired location for the tabloid size plate on the saddle, and meanscarried by the saddle and acting on one edge of the tabloid size plateto urge the plate solidly against said hooks and thereby hold the formeragainst movement including means providing a recess in the crown of saidsaddle on the opposite side of the center line from said first-mentionedrecesses, a shaft extending from one end of said saddle into saidlastnamed recess, a finger pivotally mounted in said lastnamed recess onsaid shaft, a spring between said shaft and said finger tending to urgethe latter in a direction toward the plate locating hooks carried by thesaddle, and means for rotating said shaft to raise said finger to anoperative position adjacent the edge of a tabloid size plate on saidsaddle, said spring being effective to urge said finger against the edgeof said plate and thereby resiliently urge the latter against said platelocating hooks.

9. in a machine for milling tension lock-up pockets in serni-cylindricalprinting plates, the combination comprising, a saddle providing asemi-cylindrical reference surface conforming to the curvature of theplates, means overlying said reference surface and engageable with aplate carried on said reference surface for clamping said plate on saidsaddle, and means for positioning a tabloid size plate having the samecurvature as the semi-cylindrical plate on said saddle while saidclamping means is engaged, said positioning means including platelocating hooks mounted along the crown of said saddle longitudinallyspaced on one side of the center line thereof and located for insertionin tension pockets adjacent one 12 edge of the tabloid size plate so asto define a desired locationfor the latter, a resiliently biased fingersupported on the saddle between said spaced plate hooks and facing thelatter on the opposite side of the center line of the saddle, and meansfor mounting said finger for engagement with the straight edge of atabloid size plate carried on said saddle and on said plate locatinghooks, to urge the tabloid size plate against said hooks so it is heldsolidly against movement.

10. In a machine for milling tension lock-up pockets in semi-cylindricalprintingplates, the combination comprising, a saddle providing asemi-cylindrical reference surface conforming to the curvature of theplates, means overlying said reference surface and engageable with aplate carried on said reference surface for clamping said plate on saidsaddle, and means for positioning a tabloid size plate having the samecurvature as the semi-cylindrical plates on said saddle while saidclamping means is engaged, said positioning means including meansproviding a recess on the crown of said saddle, a plate hook mounted insaid recess, means for mounting said hook in said recess for radialsliding movement from a position in the recess to a position projectingabove the reference surface ofsaid saddle, said hook being located forinsertion in a tension pocket adjacent one edge of a tabloid size plateso as to define a desired location for the latter, said last-named meansincluding a cam mounted under the hook on said saddle and movable in onedirection to engage and move said hook radially, a return spring actingon said hook. to move the latter below the saddle surface upon returnmovement of said cam; and means including a spring biased fingersupported on thecrown of said saddle adjacent said plate locating hookand movable into engagement with the straight edge of a tabloid sizeplate carried on said saddle to urge the plate against said platelocating hook and hold the plate solidly against movement.

References Cited in the file of this patent UNTTED STATES PATENTS1,908,497 Warnock May 9, 1933 2,180,732 Durham Nov. 2.1, 1939 2,190,380Horton Feb. 13, 1940 2,235,096 Becker Mar. 18, 1941 2,305,338 BarberDec. 15, 1942 2,604,017 Crafts July 22, 1952 2,732,798 Chase Jan. 31,1956 2,736,947 Faeber Mar. 6, 1956

